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Sir i am unable to find 2019-20 sample papers

Posted by Ranjana Yadav 6 years, 6 months ago

CBSE > Class 12 > Physics

1 answers

Anshul? Singh 6 years, 6 months ago

You can buy oswal sample papaer ranajana or cbse.nic.in

0Thank You

ANSWER

What is spectrum

Posted by Abhishek Chauhan 6 years, 6 months ago

CBSE > Class 12 > Physics

1 answers

Hemant Tiwari 6 years, 6 months ago

Band of visible lights is known as spectrum

1Thank You

ANSWER

Why i don't understand physics help me pls

Posted by Shravanbhai Sk 6 years, 6 months ago

CBSE > Class 12 > Physics

3 answers

Priya Dharshini ? 6 years, 6 months ago

This is problem with most of them.. even me , last year i hate physics.. i tried to understand that topic and imagined how the structure really is. Saw some videos to make it more clear... and practiced derivations atleast 5 times each one and some many numericals from ncert and sl arora.. try these things it may help u. .

1Thank You

Parul Singh 6 years, 6 months ago

Only written practice is the solution

1Thank You

S. Sri Raman Prasad 6 years, 6 months ago

Study s l arora

0Thank You

ANSWER

What are dimensional formula of magnetic field?

Posted by Didar Singh 6 years, 6 months ago

CBSE > Class 12 > Physics

1 answers

Pragati Saini 6 years, 6 months ago

M T⁻² A⁻¹

0Thank You

ANSWER

An inductance of negligible resistance whose reactance is22ohm at 200Hz is connected to a 220V, 50Hz power line. What is the value of inductance and current?

Posted by Ramsha Malik 6 years, 6 months ago

CBSE > Class 12 > Physics

0 answers

ANSWER

show on a graph the variation of resistivity with temperature for a typical semiconductor

Posted by Suchit Kahar 6 years, 6 months ago

CBSE > Class 12 > Physics

1 answers

Gaurav Seth 6 years, 6 months ago

Semiconductors : In case of insulators and semiconductors, the relaxation time τ does not change with temperature but the number density of free electrons increases exponentially with the increase in temperature. Consequently, the conductivity increases or resistivity decreases exponentially with the increase in temperature.

The resistivity of a semiconductor decreases rapidly with increasing temperature.

1Thank You

ANSWER

I m not able to do physics.......plz help me I m confused which topic to do

Posted by Palak Bhawsar 6 years, 6 months ago

CBSE > Class 12 > Physics

4 answers

Khushi Meel 6 years, 6 months ago

Do all the topics carefully and solve more and more questions.

2Thank You

Kiran??? Gautam 6 years, 6 months ago

Start from the first chapter and do it from each and every smalll derivation and topics

1Thank You

Anshul? Singh 6 years, 6 months ago

Give me the Chapter Name coming in yr EXAM

1Thank You

Suchit Kahar 6 years, 6 months ago

Just change your subject *Science* to *commerce*

3Thank You

ANSWER

Sample paper for 2020

Posted by Shivam Yadav 6 years, 6 months ago

CBSE > Class 12 > Physics

3 answers

S. Sri Raman Prasad 6 years, 6 months ago

It will release on sep-oct

0Thank You

Kiran??? Gautam 6 years, 6 months ago

Waiting

0Thank You

Khuskaran Sidhu 6 years, 6 months ago

Me too waiting ????

0Thank You

ANSWER

Please help me in thinking on topic on which i should make a project In physics working model

Posted by Aadi Ahluwalia 6 years, 6 months ago

CBSE > Class 12 > Physics

3 answers

Priya Dharshini ? 6 years, 6 months ago

Fire alarm using thermister,metal detector,tesla coil,construct half wave rectifier.. is it compulsory to do working model in investegatory ?

1Thank You

Ayushi Kothari 6 years, 6 months ago

Make water cleaning boat https://youtu.be/fqd_RcD49ME

1Thank You

Tanishq Shukla 6 years, 6 months ago

Tesla's coil, solar boat , half wave rectifier , full wave rectifier, projects related to application of pascal law such as hydraulic cranes and hydraulic arms etc.

0Thank You

ANSWER

How we can leran physics easily

Posted by Deepshikha Kumari 6 years, 6 months ago

CBSE > Class 12 > Physics

2 answers

Priya Dharshini ? 6 years, 6 months ago

U need to practice and understand the concepts.. ur imagination should be excellent in it.. see few videos to know how really magnetism or electric field works.. it would be easy for u to make diagrams and to write derivations and solve numericals...

0Thank You

Suchit Kahar 6 years, 6 months ago

Gaand maraa ke !!

0Thank You

ANSWER

Bule print of physics ,maths,chem,English for 12 board exam chpt wise

Posted by Baljot Sidhu 6 years, 6 months ago

CBSE > Class 12 > Physics

0 answers

ANSWER

A wire of resistance 2ohm is acted uppon by a deforming force so that it length is reduced to twice of its original length

Posted by Nitupawan Tamuli 6 years, 6 months ago

CBSE > Class 12 > Physics

0 answers

ANSWER

How does the mobility of electrons in a conductor change, if the potential difference applied across the conductor is doubled ,keeping the length and temperature of the conductor constant?

Posted by Harshit Yadav 6 years, 6 months ago

CBSE > Class 12 > Physics

0 answers

ANSWER

Force on a moving charge in uniform magnetic and electric field

Posted by Komalpreet Kaur Sohi 6 years, 6 months ago

CBSE > Class 12 > Physics

2 answers

Anjali Kaushik 6 years, 6 months ago

F=qE for charge in a uniform electric field and F=iBL charge in uniform magnetic field

1Thank You

Aryan Ranjan 6 years, 6 months ago

E=-V×B - i F=qE - ii E=Vd - iii Put iii in ii F=qVd or, V=F/qd Put this in i E= - FB/qd Here E is electric field B is magnetic field q is Charge d is distance

1Thank You

ANSWER

Coil of a moving coil galvanometer is wound on a metallic frame why ?

Posted by Amanpreet Kaur Randhawa 6 years, 6 months ago

CBSE > Class 12 > Physics

1 answers

Řøhăň Řąjpůť ✌️✊ 6 years, 6 months ago

to provide electromagnetic damping.

2Thank You

ANSWER

What are t.v signal and how can they received

Posted by Munni Kumari 6 years, 6 months ago

CBSE > Class 12 > Physics

2 answers

Priya Dharshini ? 6 years, 6 months ago

Radio waves are used to telecast t.v programms.. 54 hz to 890 hz

0Thank You

Muskan Agarwal 6 years, 6 months ago

No answer

0Thank You

ANSWER

What will be the force experienced by an electric dipole when placed in uniform electric field

Posted by Diwakar Kumar 6 years, 6 months ago

CBSE > Class 12 > Physics

3 answers

Shantanu Pandey 6 years, 6 months ago

Torque will act on it .. Torque=pEsinx x: is the angle that axis of dipole makes with magnetic field p: qd (d is length of dipole) and E is electric field Force will be 0 when x=0(stable) or x=180 (unstable)

0Thank You

Priyanshu Kapoor 6 years, 6 months ago

Zero force but some amount of toque is experienced

0Thank You

Deepak Singh 6 years, 6 months ago

Zero force experienced by electric??? dipole when placed in uniform electric field

1Thank You

ANSWER

What is the total marks weightage of physics numericals for this years board examinations ?

Posted by Sonalrajsingh Singh 6 years, 6 months ago

CBSE > Class 12 > Physics

4 answers

Kiran??? Gautam 6 years, 6 months ago

Really

0Thank You

Aadi Ahluwalia 6 years, 6 months ago

20-30 marks

0Thank You

Kiran??? Gautam 6 years, 6 months ago

Sirf 12-17

1Thank You

Gursharn Kaur 6 years, 6 months ago

12 - 17 marks

1Thank You

ANSWER

The force of attraction between two charges +30×10^-9C separated by a distance of 0.20 m is found to be 5×10^-5 N. Find the relative permittivity of medium.

Posted by Sonalrajsingh Singh 6 years, 6 months ago

CBSE > Class 12 > Physics

1 answers

Nishu Goyal 6 years, 6 months ago

It might be 1.38 multiply 10 raise power 13

0Thank You

ANSWER

The equivalent capacitance of the combination of three capacitors each of Capacitance C between points A and B is -(a)3C (b)C/2 (c)2C (d)C. Check out the diagram from goolge.

Posted by Arjun Ghosh 6 years, 6 months ago

CBSE > Class 12 > Physics

0 answers

ANSWER

Why magnin wire is only used in potentiometer experiment?

Posted by Sanjay Choudary 6 years, 6 months ago

CBSE > Class 12 > Physics

3 answers

Aryan Ranjan 6 years, 6 months ago

It exhibits very weak dependence of resistivity with temperature. It's resistance value would Change very little with temperature.

1Thank You

Jk Verma 6 years, 6 months ago

Being an alloy , it has high resistivity and low temperature coefficient of resistance/resistivity.

2Thank You

Amanpreet Kaur Randhawa 6 years, 6 months ago

Because they posses high specific resistance and low temperature cofficient

3Thank You

ANSWER

Is ray optics and wave optics coming in the board exam??

Posted by Anushree Agarwal 6 years, 6 months ago

CBSE > Class 12 > Physics

6 answers

K@Łp@N@ $Øđh!?? 6 years, 6 months ago

Yes

0Thank You

Saurabh Gupta 6 years, 6 months ago

Yes both are coming some topic are deleted

0Thank You

Kiran??? Gautam 6 years, 6 months ago

Yeh it is

1Thank You

Nishu Goyal 6 years, 6 months ago

Yes it is the max. Mark containing unit

1Thank You

Hritwik Raj 6 years, 6 months ago

Ys , it is in syllabus

1Thank You

Shruti Kamal 6 years, 6 months ago

Yes.......

1Thank You

ANSWER

In youngs double slit experiment

Posted by Dhruba Jyoti Lahon 6 years, 6 months ago

CBSE > Class 12 > Physics

2 answers

Dhruba Jyoti Lahon 6 years, 3 months ago

OK wait

0Thank You

Nishu Goyal 6 years, 6 months ago

Pura question toh likho kam sae kam

0Thank You

ANSWER

What sort of questions will objective type ques include ❓

Posted by Khuskaran Sidhu 6 years, 6 months ago

CBSE > Class 12 > Physics

3 answers

Saurabh Gupta 6 years, 6 months ago

Mcq questions number are increase by 20

1Thank You

Priya Dharshini ? 6 years, 6 months ago

Mostly numericals, and few give reasons... questions xan be asked... u can check in sl arora there are few sample of objective type questions..

3Thank You

Řøhăň Řąjpůť ✌️✊ 6 years, 6 months ago

conceptual question might be

2Thank You

ANSWER

Arihant chapter wise or Rachna Sagar chapter wise?

Posted by Divyansh Dubey 6 years, 6 months ago

CBSE > Class 12 > Physics

2 answers

Saurabh Gupta 6 years, 6 months ago

Arihant is best

0Thank You

Řøhăň Řąjpůť ✌️✊ 6 years, 6 months ago

Arihant is best

2Thank You

ANSWER

Define of mutual and self induction in simple language...

Posted by Hritik Gupta 6 years, 6 months ago

CBSE > Class 12 > Physics

3 answers

Premesh Tyagi 6 years, 6 months ago

If emf is induced due to change in the current of own coil is called self induction if emf is induced in 1 coil due to change in current of other coil this process of induced emf is known as mutual induction

2Thank You

Amber Mishra 6 years, 6 months ago

Self induction- It is a phenomena when there is change in current then coil oppose them and induced emf of itself. Mutual Induction-It is a phenomena in which an emf is induced in secondary coil due to change in current of primary coil

2Thank You

Khuskaran Sidhu 6 years, 6 months ago

Self induction - production of induced emf in one coil in itself Mutual induction - production of induced emf in S coil due to change in current in P coil

2Thank You

ANSWER

Ac chapter all expression

Posted by Jagganath Rathod 6 years, 6 months ago

CBSE > Class 12 > Physics

1 answers

Afjal Ansari 6 years, 6 months ago

Electric current

0Thank You

ANSWER

Relation between current and drift velocity

Posted by Nidhi Lal 6 years, 6 months ago

CBSE > Class 12 > Physics

4 answers

Premesh Tyagi 6 years, 6 months ago

Current rate of flow of charge per unit time is called current and drift velocity the average velocity with which free electron move in a conductor on application of potential difference is called Drift velocity

2Thank You

Bhaghwan Kamble 6 years, 6 months ago

as I =neaVd So I is directly proportional to Vd

0Thank You

Gaurav Seth 6 years, 6 months ago

FLet l is the length of the conductor and A uniforms area of cross-section.
Therefore, the volume of the conductor = Al

If n is the number of free electrons per unit volume of the conductor, then the total number of free electrons in the conductor=A/n.

If e is the charge on each electron then total charge on all the free electrons in the conductor

Q=A/ne (1)

Let a constant potential differences V is applied across the ends of the conductor with the help of a battery

The electric field set up across the conductor is given by

E=V/l

Due to this field, the free electrons present in the conductor will begin to move with a drift velocity vd towards the left hand side of the conductor.

Thus the time taken by the free electrons to cross the conductor is

t=l/vd (2)

As current I=q/t (3)

By substituting equation (1) and (2) in equation (3),

We get

I=Alne/l/vd

Or I=Anevd (4)

Since A,n and e are constant

I∞vd

Hence the current flowing through a conductor is directly proportional to the drift velocity.

Explanation and Example. In a conductor there are large number of free electrons. When we close the circuit , the electric field is established in the circuit with the speed of electromagnetic wave which causes electron drift at every portion of the circuit. Due to which the current is set up in the entire circuit instantly .The current thus set up does not wait for the electrons to flow from one end of the conductor to another end. It is due to this reason, the electric bulb glows immediately when switch is on.

1Thank You

Uday Mann 6 years, 6 months ago

I=naVe

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All 1 marks questions are mcq in physics board exam 2020?

Posted by Amit Kumar 6 years, 6 months ago

CBSE > Class 12 > Physics